Electromagnetic vibrator.



C. H. ADAMS.

ELECTROMAGNETIC VIBRATOR.

Patented Oct. 31, 1916.

2 SHEETS-SHEET I.

' C. H, ADAMS.

ELECTROMAGNETIC VIBRATOR.

APPLICATION FILED FEB. 18. 1916.

Patented Oct. 31, 1916.

2 SHEETS-SHEET 2.

E Y 7 [fa/62%" G/ZQFkSHQZcLHUS mam UNITED STATES PATENT OFFICE.

CHARLES ADAMS, OF MUSKEGON HEIGHTS, MICHIGAN.

ELECTROMAGNETIC VIBRATOR.

Specification of Letters Patent.

Patented Oct. 31, 1916.

Application-filed February 1a, 1916. Serial No. 79,054.

- cost of construction of devices of this character. I 1

Other and further objects of my invention will become readily apparent, to persons skilled in the art, from a consideration of the following description when taken in conjunction with the drawings, wherein Figure 1 shows one use for which the vibrator is adapted. Fig. 2 is a side elevation of a modification of the preferred device. Fig. 3 is an end view thereof showing parts in section. Fig. 4 is a section taken on line 44 of Fig. 2. Fig. 5 is a transverse section of the preferred form of the device, taken on line 55 of Fig. 6. Fig. 6 is a central Vertical section of the preferred form of the device.

In all the views the, same reference charactors are employed to indicate similar parts.

Electro magnetic vibratory motors capable of striking sharp, rapid and limited, snappy blows are employed in the arts for many uses. Foundry men find them convenient for use to impart to gated patterns, or to flasks within which patterns may be contained, light active vibratory motion to overcome the coalescence of the pattern with the sand, within which it may be embedded, so that the pattern maybe more readily lifted therefrom.

In Fig. 1, 5 is a mold flask, 6 the cope and 7 the drag. I have shown one form of the vibrator 8 connected to the drag, at one corner, and another one 8 connected 'at the other corner, so that the vibrations imparted thereto by the respective devices, will be atv employed for this'purpose and connected to the drag or cope in any particular mannor that may be desired by the user, or the ylbrator may be connected to a gated patern.

I have shown a circuit connected. with an alternating current generator 9, including the vibrators 8 and 8'. Of course the vibrators may be connected in parallel, if desired, as the particular manner of connectlng them in circuit is not part of my invention. I

Specifically, the vibrator 8 consists of a core 10 made of U-shaped laminae, preferably punched from suitable sheet metal and comprising legs 11 and 12 and an integral yoke 13. The laminae are held together, at suitable intervals, by rivets 14. One leg, to wit; the leg 11, is surrounded by an electric coil 15. An armature 16, is made inthe same manner, of a series of sheets or plates of magnetically permeable material, and built up to be equal in width to the width of the cores of the electro-magnet, is held together at one end, by U-shaped clip 17 which serves as a hammer and is preferably made of hardened steel or the like, to withstand the force of impact of the blows upon the hardened and adjustable anvil 18. The armature is perforated, at one end, as at 19, with a hole somewhat larger than the pivotal rivet 20. The rivet passes through an upwardly projecting support 21 which is riveted to the end of the leg 11 of the electromagnet, as at 22, affording a pivotal support for the armature 16. A frame 23, for attaching the device to whatsoever it is desired to impart the necessary vibration, comprises a projecting lug 24, perforated for an attaching bolt, .as at 25, and having side members 26 that are integral therewith, and which embrace the leg 12 and are riveted to the leg of the electro-magnet, as at 27. To strengthen the frame 26, a rib 28 joins the lug 24 with the side members 26 and upon its upper end is enlarged, as at 29, to contain the adjustable anvil 18. The enlarged portion 29 is split,as at 30, and contains a contracting screw 31, which is threaded into the part 29 of the enlarged member. The lower end of the anvil 18 is screw threaded, as at 33, whereby it may be vertically adjusted in the enlarged portion 29 of the rib. The nut 34 overlies the anvil and is the means for holding it in adjusted position, until the screw 31 canbe turned to clamp it tight in the position in which it has been adjusted. Overlying the armature is a stirrup 35, preferably rectangular in shape, and an integral part of the frame 23, preferably made of diamagnetic material, such as brass or the like, for the purpose of limiting the upward stroke of the armature 16. An open helical spring 36 overlies the anvil 18, and rests upon the nut 34 and upon the underside of the armature 16, whereby to yieldingly hold the armature in retracted position.

When the electro-magnet is energized, the armature 16 is attracted and the U-shaped clip 17 strikes the upper end of the anvil 18 just before the lower edge of the armature comes in'contact with the upper surface of the leg 12, thereby producing a sharp active impact and imparting a vibratory movement to the device, and to the article to which it may be attached.

As shown in Fig. 1, either form of the device is assumed to operate by the effect of an alternating or impulse current.

By making the hole 19 through the support 21 relatively large, of Fig. 2, the rear end of the armature 16 may lie in contact with the upper end of the leg 11 of the magnet core, thereby reducing the air gap between the core and the armature to the lowest extent and causing a relatively heavy flux of magnetic lines through this portion of the magnetic system.

. The preferred form of vibrator is shown in Figs. 5 and 6. 40 represents the vibrator, 41 the base and 42 the projecting lug by which it is to be connected to the flask or to a pattern. A casing cover 43, which may may be made of metal, bakelite or the like is secured to the base 41 by screws 44 that pass through interiorly projecting lugs 45. Other lugs 46 may be employed to secure the I device to a flask, or within which to secure electrical terminals. The coil 47 is wound upon an insulating spool 48 and they are both mounted upon a metal spool 49, axially split as at 50 to prevent parasitic currents in the spool. The laminated magnetic core 51 consists of a series of relatively thin strips of iron 52, bcnt sothat the yoke portion 53 lies in a horizontal position substantially parallel with the base 41, and across the opening in the spool or coil, the other end 54 being bent radially toward the center of the coil and. terminating, as at 55,

near the yoke 53. The other magnetic meme ber 51 is bent in a similar manner to provide a yoke member 53 and a vertical member 52 and it is also bent near the top of the spool in a radial direction to provide a part 54 which enters the interior of the spool and terminates at 55 and at this point the two ends 55 and 55 are secured together by means of a rivet 57, or the like. Screws 58 and 58 pass through the base 41 and through the yoke members 53-53 and through the flange of the spool 49, to hold the assembled parts in place.

The alternations or impulses of electric current passing through the coil 47 will cause the ends 55-55 of the composite'co-re to strike the yoke 53 a series of sharp blows which will continue as long as the-circuit remains closed through the magnet coil 47. The resiliency of the cores 54-54 is suflicient to retract the core member from contact with the yoke during the intermission between the alternations or impulses of current, so that .a separate special spring, such as the spring 36, shown in Fig. 3 is not necessary with this form of device.

When the end 55 of the core is in contact with the yoke 53 there isa double magnetic path thus closed through the magnetic system. This form of device is, therefore, very efiicient, preventing excessive leak of the magnetic flux, owing to the peculiar construction of the core. It is also very efficient because the blow is struck on a solid portion of the structure in immediate line with the attaching lug 42.

\Vhile I have herein shown and described two forms which my invention may take it is manifest that other forms and variations, within the spirit and scope of the appended claims may be made without departing from my invent-ion.

Having described my invention, what I claim is:

1. A device of the character described comprising a support, an electromagnet coil having a through axial opening, a flexible core having a base portion underlying the magnet coil, the end portionsof the core projecting from the base portion extending up the outer side of the magnet coil at diametrically opposite points, across the upper end thereof, and downwardly into the axial opening into close proximity to the base portion, .means for securing together the downwardly projecting ends of the core and means for fastening the magnet coil and core base to the support.

2. A device of the character described comprising a support, an electromagnet coil having a through axial opening, a, flexible core having a base portion underlying the magnet coil, the end portions of the core projecting from the base portion extending up the outer side of the magnet coil at diametrically opposite points, across the upper end thereof, and downwardly into the axial opening into close proximity to the base portion, the downwardly projehting portions of In testimony whereof I hereunto set my the core being spaced apart at their upper hand in the presence of two subscribing witends outside the coil and joined at their nesses.

lower ends Within theaxial opening in close CHARLES H. ADAMS. proximity to the base portion and means for In the presence of A fastening the magnet coil and core base to W. H. HOWE, the support. AGNES E. HOWE. 

